Colorado brewery lore is full of stories about mistakes that turned into successes -- batches of beer that turned out well despite the odds. Of course, Colorado brewery lore is also full of stories about carefully planned beers that went horribly wrong, but those stories are more often that not dumped down the floor drain like the beer itself.

Boulder Beer will begin telling one of the success stories, in liquid form, when it releases Bad Moon Risin' Double Black IPA today at 4 p.m. -- a beer that was never supposed to happen.

Here's what went down: Late last year, one of Boulder Beer's brewers finished milling nearly 5,000 pounds of grain for use in a batch of Mojo Risin' double IPA. He then filled up a grain storage hopper above the mill with 3,200 pounds of grain needed for the batch of Planet Porter that was next on the brewing schedule. When he knocked off for the day, the brewer left a note for the next guy on duty, explaining what he had done.

But since Boulder Beer's 28-year-old grain miller usually can't handle all 4,000 pounds of barley needed for Mojo Risin' at once, the brewers usually have to do it in two batches. The next brewer on duty misinterpreted the note and assumed that the grain waiting in the hopper was for the Mojo rather than the Planet Porter.

So he milled and mixed in a good portion of the Planet Porter grain with the Mojo grain before realizing what was going on.

When they realized the mistake, the brewers decided to use the opportunity to make a big, new beer. "They continued through the brewing process, experimenting with a unique hop recipe that would pair well with the odd grain combination," Christie explains. "Having never prepared a small batch on our pilot system, the brewers weren't sure exactly how the beer would turn out, but we couldn't be happier with it."

They ended up with a fifty-barrel batch they're calling Bad Moon Risin' Double Black IPA -- and since they don't know exactly how much grain was used and weren't working off of a recipe, they won't ever be able to duplicate it exactly. Weighing in at 12 percent ABV, it is the strongest beer the brewery has ever made on a large scale.

It will also be the most limited production beer that the brewery has ever put together: there are a total of eighty kegs that Boulder Beer will serve in its pub and distribute to "cool places throughout Boulder, Denver, and the rest of the country." Keep up with Boulder Beer's Facebook page to find out where, Christie says.

Boulder Beer estimates that they used somewhere between 6,300 and 6,700 pounds of grain, including Caramel Malt, Wheat Malt and black malt, along with Centennial and Nelson Sauvin hops.

Our brewers actually work really hard to make sure this type of stuff doesn't happen," Christie says. "From time to time, there will be something minor like labels that are fed-in upside down on the bottling line, but this was one of the biggest 'oops' moments our brewers have seen in a really long time."